Method and apparatus for mounting and faceting gemstones

{
  "publication_number": "US5085011A",
  "country": "US",
  "kind": "A",
  "title": "Method and apparatus for mounting and faceting gemstones",
  "abstract": "Apparatus for grinding or polishing flat facets of gemstones comprising a mirror lap wheel base adapted to be mounted to a rotary drive and a lap film adapted to be mounted flushly upon the mirror lap wheel base.",
  "claims": [
    "1. Apparatus for grinding or polishing flat facets of gemstones comprising, in combination, a mirror lap wheel base having mounting means for mounting the wheel base to rotary drive means, and a lap film adapted to be mounted flushly upon said mirror lap wheel base, whereby a flat facet to be worked while mounted to a dop of a faceting machine may be placed upon the mirror lap wheel base and a reflected image of the facet observed for verification of flush contact with the base and subsequently worked by the lap film mounted flush to the base.",
    "2. A method of grinding or polishing a flat facet of a gemstone comprising the steps of placing the facet upon a mirror lap wheel base, observing the reflected image of the facet, orienting the gemstone as needed until the reflected image is substantially that of the entire facet at a determined orientation thereby verifying flush contact being established between the entire facet and the mirror lap wheel base, removing the gemstone from the mirrored lap wheel base, mounting a lap film flushly upon the mirrored lap wheel base, rotating the lap film covered base, and bringing the gemstone facet into working engagement with the rotating film covered base with the facet substantially at the determined orientation.",
    "3. A lap wheel base for use in grinding or polishing flat facets and which comprises a generally disc-shaped mirror having an axis of rotation and a flat support surface and means for mounting said mirror along said axis to a rotary drive device, whereby a workpiece facet may be placed upon the mirror flat support surface and its degree of flush engagement with the support surface visually observed and the facet then ground or polished with a grinding or polishing material mounted upon the mirror support surface with the base rotated by a rotary drive device.",
    "4. The lap wheel base of claim 3 in combination with a lap film mounted directly upon said mirror support surface.",
    "5. The lap wheel base of claim 3 wherein said disc-shaped mirror has a transparent portion one surface of which is coated with a reflective material and the opposite surface of which is said support surface."
  ],
  "cpc": [
    "B24B 9/16"
  ],
  "assignees": [
    "SMITH C R"
  ],
  "filing_date": "1989-10-16",
  "publication_date": "1992-02-04",
  "grant_date": "1992-02-04",
  "priority_date": "1987-07-01",
  "application_number": "US-42200889-A",
  "family_id": "26749061",
  "citations": [
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  ]
}